Panda Genetic Fingerprinting

Using Genetic Fingerprinting to save the Panda might seem like a crazy idea but it's an idea that might have legs! The giant panda is one of the rarest animals in the world and is considered to be on the brink of extinction. Giant pandas have been kept and bred in zoos for many years now. In many areas, Panda's are on breeding programmes so they could, one day, be released into the wild.

Unfortunately, zoo life doesn't come worry free. There's the issue that with small populations, genetic variation is reduced. This basically means they could well struggle when they're released into the wild. Having said that, Pandas find it difficult to reproduce in captivity.

Scientists can only guarantee that a female will get pregnant through pretty much carrying out Panda IVF. When they do so, they use sperm from several males. One problem with this is that, who's the father? Identifying who the father is can then help the scientists to identify how genetically different pandas are.

Their method of obtaining DNA samples is strange, to say the least!! They collect around

10 Panda faeces can be collected from the wild. The faeces contain DNA from the panda, from the bamboo on which they feed and from bacteria. The DNA is then put through the 

polymerase chain reaction (PCR). The primers used attach only to the panda DNA because of complementary base pairings.

The DNA from this, then goes through genetic fingerprinting. This is where the genetic sequences are read (ie GATC etc etc). Collating an idea of what happens in the wild, pandas can then be individually identified.

How this happens, is quite a complex scientific process. DNA is first cut using a restriction enzyme. This cuts the DNA at specific points. Gel Electrophoresis then separates the strands according to length (so mass as well). A process called Southern blotting then makes the strands single stranded. A DNA probe (which is complementary to part of the DNA strand) is then added. The probe will act as some kind of marker - it could be radioactively marked or fluorescent.

What are mutagenic agents?

Mutations are spontaneous errors where DNA is misread during replication. There are some things which can increase the rate of mutations. These include UV, ionising (high energy) radiation, some chemicals such as benzene and some viruses are all examples of mutagenic agents. They work by

acting as a base. Chemicals called base analogs can then act as a substitute for a base during DNA replication.

What is siRNA?

siRNA is short for small interfering RNA and acts to 'silence' a gene. It's short as its name suggests, they're usually only around 21 nucleotides long. They're also double stranded. This means that they are made up of a series of two complementary base pairs.


siRNA is called "interfering" because it disrupts translation (a part of protein synthesis which takes place within the cytoplasm). The siRNA and accosiated proteins bind to target mRNA
proteins cut mRNA into sections so it cant be translated.


siRNA prevents expression of the specific gene as its protein cant be made during translation so the protein isn't made.

DNA (deoxyribonucleic acid) - Profile

What is it?


As James Watson and Francis Crick famously said - "the secret of life". It's a vital part of any species, how it functions and the reactions that are carried out.



When was DNA discovered?



1953, by James Watson and Francis Crick - although as with any scientific discovery they were working as part of a team. Rosalind Franklin is often credited for her contribution to the discovery of DNA.



What's it made from?


The backbone of DNA if you like is made from sugar and phosphate. The 'rungs' if you like are made from bases - adenine, cytosine, guanine and thymine which form complementary base pairings. As its full name suggests, there's also deoxyribose sugar which makes up the structure.

These complementary base pairings combined with the deoxyribose sugar and phosphate make up the 'nucleotide', lots of these join together make up one of the DNA strands. Because there are lots of these joined together - DNA is a polynucleotide.





How much DNA do we have?


A LOT! Although sequencing human DNA is in its very early stages, we do know that human DNA has around three billion base pairings.



Can we do anything with DNA?
Surprisingly, yes. This year Barack Obama announced plans to sequence the genome of around 1 million people in the US in the hope scientists can use this information to create advanced treatments, targeting specific regions of our DNA.


How do we make more of it?


You'll see in more detail exactly how DNA is replicated in my Christmas countdown posts, but in short, DNA is copied to a molecule called RNA. This is because the organelles for protein synthesis are found in the cytoplasm but DNA is bound in the nucleus. This process of copying the DNA to RNA is called transcription. Once the RNA has left the nucleus, it joins to a ribosome where it can then make a protein. This is called translation.

How is our genetic code stored?

Genes define who we are. This genetic information is coded into our DNA, which has four bases, A, C, G and T that pair up in complementary base pairings. These bases are like instructions to make a protein. Humans have an estimated 20,500 genes that vary in length in each cell.  And if you were to stitch all 46 human chromosomes they would measure nearly 2m. They determine all aspects of how the body works, from your physical appearance to the biochemical reactions that happen deep inside your body.

Every individual has two copies of every gene, one which is inherited from each parent. Within your body there are several alleles of each gene. Alleles are different forms of the same genetic code with minor alterations within the code. Overall these alleles perform the same function, but the subtle differences within the code makes each of us unique.

Inside each of our cells ( except red blood cells) is a nucleus where our genetic information is stored. The deoxyribonucleic acid (DNA) is made up of A (adenine), C (cytosine), G (guanine) and T (thymine). Francis Crick who was partly credited with the discovery of DNA put it "DNA makes RNA, RNA makes proteins and proteins make us" 

RNA is ribonucleic acid which is a temporary copy of the DNA which enables it to be carried out into the cytoplasm (outside the nucleus) to the ribosomes which is where the proteins are made. This copying means that each cell can retain the same DNA with the new cell being identical to the first.